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HTML How to Make a Website Creating HTML Content Include External CSS

Erik Nuber
Erik Nuber
20,629 Points

when to use <link> versus <link />

I have been looking at a lot of code trying to further my understanding, specifically the difference between canonical and alternate as a relationship value and have noticed that the <link> tag is written two different ways based on the websites you visit but, I can't find an explanation as to why.

First is how it is shown in this video

<link rel="stylesheet" href="style.css">

Than I have seen it written out as

<link rel=”canonical” href=”http://www.example.com/url-a.html” />

This second one has a floating / at the end and, I have seen several pages where even the first example has / after it. Is this for an older version of HTML? For some other purpose? I have also wondered if this is simply a way of closing the link since it is self closing and, maybe other tags like <img> that are self-contained should also have this.

2 Answers

"Under XHTML 1.0, empty elements such as <link> require a trailing slash: <link />".

https://developer.mozilla.org/en-US/docs/Web/HTML/Element/link

So for example if you were using XHMTL 1.0 you would have to do the same with the img tag

 <img src="cat.jpg" /> 

XHTML is more strict but you don't see it too often anymore. If you'd like to know more about it: http://www.webstandards.org/learn/articles/askw3c/oct2003/

Erik Nuber
Erik Nuber
20,629 Points

Great thank you, I appreciate the quick answer.